In what way have you checked for leaks?
How quickly does it loose coolant etc? and or how much needs to be topped up?
If its been pressure tested..you need to let it sit under pressure for at least 15minutes..if it holds..then the coolant system doesnt have a leak..as the pressure test should help ID leaks that can occur if the engine is hot when things expand..but if nothing is seen or the pressure guage doesnt move after 15minutes..then the system is fine...that would leave maybe possible bad expansion tank cap maybe allowing the coolant to boil and evaporate....so you may want replace that and see if that helps....Normally during a engine swap you will need to reconnect coolant pipes thats why is best to recheck those are tight..aswell as the radiator too..but if all these are dry and tight then you can sort of focus elsewhere..like i say with the cap as above... The fans or an electrical fault shouldnt coolant loss...
Ok..no problem...In the mean time if you could leave a rating for me before you log out..much appreciated
Unless the cap is faulty - i cant see how it could loose that amount of coolant but not show any signs of overheating or even a sign of leak somewhere..if the pressure test was done correctly - that will only leave either the system maybe over pressurizing exhaust gas leaking into the system thus forcing the coolant out..a block test would check for that...
You need a block test kit - it test for combustion leak and can verfiy that the coolant system maybe overpressurising.. in the kit you have tube and suction bulb on the top..you fill the tube with the special dye..fit it onto the neck of the expansion tank..and squeeze the bulb a few times..then start the engine up..whilst its running watch to see if the dye changes colour to Yellow then you have internal leak..if its stays Blue then you have no leak...Having said that any good garage should have this kit..so it maybe worth enquiring locally to have it done than buy the kit yourself.....if its still Loosing coolant then the cap might be your problem..it could also be worth making sure the Oil is ok and water not getting into that instead...have you checked the heater matrix and around the floor area just to be sure it not leaking into the cabin